By IANS, [RxPG] Islamabad, May 19 - Pakistan's Supreme Court has directed that a senior Lahore High Court judge conduct an inquiry into court official Syed Hammad Raza's killing, cancelling a probe ordered at the level of an Islamabad District and Sessions judge.

Raza, an additional registrar of the Supreme Court, was gunned down by two men at his residence here Monday. He was tipped to depose before the Supreme Court that is hearing a clutch of petitions by and on behalf of suspended Chief Justice Iftikhar Mohammed Chaudhry.

The apex court said it had already taken suo motu cognisance of Raza's killing. Justices Javed Iqbal and Abdul Hameed Dogar, in an order, cancelled the notification by the Interior Ministry appointing Islamabad District and Sessions Judge Mirza Rafiuz Zaman as inquiry officer.

Hammad's wife, Shabana Raza, said her husband was killed because of his association with the chief justice.

Shabana received a telephone call from President Pervez Musharraf assuring her that the government would do everything to nab the culprits and the family would receive justice, Associated Press of Pakistan - news agency reported.

Chaudhry's lawyers told Daily Times that their client had confirmed that Raza would have appeared before the court as a defence witness. Therefore, he viewed the murder with suspicion.

Supreme Court Bar Association president Munir A. Malik, who is spearheading a campaign for Chaudhry, said the latter believed that it was a target killing.

Investigators have, however, rejected the possibility of it being a target killing and also ruled out sectarian motives being behind it. Police declared the incident an armed robbery after preliminary investigation.